The 7 rules of carbon offsetting your flights

Suppose you have to fly, or you use a gas-guzzling SUV. Is there any point in carbon offsetting? Yes, and it's not as dear as you might think. But what sort should you use?

The 7 rules of offsetting are:

1. It doesn’t let you off the hook. You’ve helped global warming. And:

2. As soon as you do the thing that needs offsetting, like flying, those pesky greenhouse gas (GHG) molecules are up there helping to warm the planet.

3. Therefore: action needs to be as immediate and swift as possible.

4. So waiting around for a tree to grow is not an option esp. if you have no idea what will happen to it (fire/disease, etc.). It will take ages for it to recoup the CO2 from the skies.

5. The offsetting action needs also to be additional to what you’d do otherwise, or it makes no diff., right?

6. And it needs to start as soon as possible to start compensating for those GHGs you sent up.

7. Speed also includes the time it takes for the GHGs that would have gone into the sky if your offsetting hadn’t happened to reach the total equivalent of the GHGs caused by your flight: the faster the better.

Example: solar lanterns in Africa

I buy a single solar lantern from solaraid.org that displaces a kerosene lantern used by a family in rural Uganda for £5.

I have no idea how long it takes for that family to get the lantern, but it’s good that they do for other reasons (their health, and their kids can study after dark (6pm)).

Once they get it, I don’t know how often they’ll use it. So I don’t know how long it will take to displace the kerosene-emitted GHGs they were using to the equivalent of the GHGs caused by my flight.

But I do know that even though Jremy Leggett says that 1 lantern offsets a flight to Istanbul from London in an average of two years, the more lanterns I buy the faster the offsetting will happen.

If I buy 4, then in 6 months; 8 in 3 months. So I could buy 8 for £40. That would be a very good solution.

Example: solar roofs for community buildings in Wales

I could invest in solar panels on community buildings in egni.coop’s share issue. That's a social benefit as well as an eco-benefit.

That would be additional if I wasn’t going to do it otherwise.

Egni will put up the panels on community buildings in Wales within about 6 months, I reckon.

And you’d get a return on your investment.

Every 4kWe of PV (photovoltaic panels), will save around 1124Kg of CO2 in one year based on this: https://carbonintensity.org.uk/#regional

Ask Dan McCallum at Egni.coop how many kilowatts of PV a given amount of investment would buy if you want to know. (I made their website btw).

That would be a nice thing to do to.

Just two years away: cheap, easy to make, 3rd generation solar cells

In 2018, the long-promised “third generation” of solar cells will be ready to come to market. These are very different from the solar panels we see around us today. Transparent, lightweight, flexible and highly efficient, they will be able to be applied to windows, metal, polymers (as in cladding) or cement, effectively turning buildings into energy generators.

They can work in lower light conditions than current solar technologies, and don’t have to face the sun.

The technology is known as perovskite solar cells. Recently, a research team headed by Professors Michael Grätzel and Anders Hagfeldt at the Ecole Polytechnique Fédérale de Lausanne established a new world record efficiency for the cells, with a certified conversion efficiency of 21.02 per cent, increasing from 3.8 per cent in 2009, making this the fastest-advancing solar technology to date.

With low production costs, many start-up companies are promising modules on the market by 2017.

Dyesol Limited is one such company focused on commercialising these cells. Dyesol has been around for many years, longer than most of its competitors, and has secured several key patents in the field.

Three years ago it switched its research and development from dye-sensitised technology to perovskite because of its advantages.

Based in Australia, its chief executive, Richard Caldwell (above), recently released a levelised cost of energy study (which enables comparison with the market price of other energy technologies). This demonstrated costs of between 9.6 and 12 Australian cents per kilowatt-hour for the panels when manufactured and utilised at a relatively small scale. This compares to around 10-11 cents for conventional solar – about the same, but before mass production.

At the end of last year Caldwell reached an agreement with the Australian Renewable Energy Agency to receive $450,000 funding support to progress the technology towards scalable manufacture and mass commercialisation. ARENA has established a production cost of 25 cents per watt.

“The payback period for installation is a matter of a few months, as they are less energy intensive to produce than the current (usually silicon based), which take several years,” Caldwell says.

“This is extremely exciting, as it allows us to transition to a clean energy society without any subsidies from the government.

“BIPV – building-integrated photovoltaics, in other words putting solar power generation on the surface of buildings – is the holy grail of the industry and because perovskite is ultra-thin it can easily be incorporated in buildings,” he said. “But that’s longer term. We will first produce a free-standing unit for market entry, then integrated.”

The company publishes quarterly updates of progress to demonstrate progress. Caldwell says that its next landmark later this year is “the production of panels about one metre square”, with countries like Turkey partnering to produce them.

“By 2018 we hope to be in mass production of this new product.”

The first product will feature a glass substrate, allowing light through to the interior of the building. The following year, metal-printed panels will be on the market, the company says.

Australian support

Dr Richard Corkish, chief operating officer at the Australian Centre for Advanced Photovoltaics, which has been responsible for many of the improvements in silicon solar panels the world uses today, told the ABC: “Most of the important advances in solar cell work in the past has been in making incremental improvements on the same old technology that [was] invented way back in the 1950s, but [is] now much, much better.

“[Perovskite] has captured the excitement of the whole photovoltaic research community. This material might in the future offer an alternative to silicon for the main solar cell material. Our research partners – Monash University and the University of Queensland in particular – are at the forefront of this area in Australia.”

Caldwell says “the new political regime in the Australian government is more favourable to us and the Turkish government is also very supportive.”

He welcomed Bill Gates’ recognition of the technology during the Paris climate talks, when Gates joined 27 other wealthy investors to start a new investment fund called the Breakthrough Energy Coalition, to push more public and private sector funds to clean energy technology.

Gates called PSC “disruptive” and said: “When people start talking about perovskites, painted solar applications etcetera, a lot of it is down to the physics, so the majority of the money will flow through the fund.”

The technology

The most commonly studied perovskite absorber is methylammonium lead trihalide, which uses a halogen atom such as iodine, bromine or chlorine.

Unlike traditional silicon cells, which require expensive, multistep processes conducted at high temperatures (>1000 °C) in a high vacuum in special clean room facilities, the organic-inorganic perovskite material can be manufactured with simpler wet chemistry techniques in a traditional lab environment.

Methylammonium and formamidinium lead trihalides have been created using a variety of solvent techniques and vapour deposition techniques, both of which have the potential to be scaled up with relative feasibility. These techniques reduce the need to use so much polluting solvents.

Issues yet to be resolved are around stability, as the material can degrade, reducing its efficiency.

Dyesol is developing and testing this. Its most recent newsletter, published last week, announced that a test strip passed 1000 hours at 85°C with a loss of under 10 per cent. That is still a lot, so work is underway to reduce this deterioration with different types of encapsulation. To be fair, early silicon panels suffered from a similar problem.

A related challenge is cheap and environmentally friendly electricity storage, enabling solar electricity to be used also at night.

But for now, having been heralded for a long time, very cheap solar power that lets every building or object coated with it generate electricity is now within reach.

David Thorpe is the author of:

• Solar Technology: The Earthscan Expert Guide to Using Solar Energy for Heating, Cooling and Electricity


• The ‘One Planet’ Life: A Blueprint for Low Impact Development


• Energy Management in Buildings: The Earthscan Expert Guide


• Energy Management in Industry: The Earthscan Expert Guide


• Sustainable Home Refurbishment: The Earthscan Expert Guide to Retrofitting Homes for Efficiency

British building owners can now make money by generating renewable heat

The first scheme in the world that will pay owners of domestic buildings for generating renewable heat has been launched in the UK by Energy Minister Greg Barker (seen right with MP Chloe Smith opening a 'Mr Renewables showroom' at the beginning of April).

Like feed-in tariffs for generating renewable electricity from technologies such as photovoltaic solar panels, the financial incentive scheme offers householders a fixed amount per kilowatt-hour generated from various technologies, even though the heat is only consumed in the home and not made available for others (as with home-generated electricity that is fed into the electric grid).

Called the Renewable Heat Incentive, it is based on a similar scheme for business, the public sector and non-profit organisations, that has been in operation for some time in the UK, as well as a smaller domestic scheme aimed at solid-walled, hard-to-heat homes, called the Renewable Heat Premium Payment.

Property owners apply to all schemes through the Energy Saving Trust, a government-sponsored body which promotes energy efficiency and renewable energy at the domestic scale.

The purpose of the RHI is to stimulate the renewable heat industry in the same way that feed-in tariffs have done for the solar PV industry. This has seen remarkable growth in the last four years with the cost of a typical PV system installation dropping by more than half.

The UK Government and industry body the Solar Trade Association (STA) have a target of covering over one million roofs with solar thermal and solar PV panels by the end of 2015. Over 200,000 solar thermal systems are already installed in the UK.

Global capacity for solar thermal is over 200GW - around double global installed capacity of solar power. The technology is proven and well established across Europe and elsewhere, and back in the days of previous support systems when grants were offered for installation of many types of renewable energy technologies, solar thermal was by far the most popular technology of choice for householders.

Stuart Elmes, Chair of the Solar Thermal Working Group at the STA, welcomed the launch of the RHI, saying: “Solar heating is popular with householders and quick to install, integrating easily with existing heating systems. We calculate that the returns from solar water heating are similar to those from solar power when you take into account the high price inflation for gas and heating oil.”

Paul Barwell, Chief Executive of the STA said: “With the launch of the Domestic Renewable Heat Incentive the final piece of support for household solar technologies slots into place. Together with the Green Deal for insulation improvements and the Feed-in Tariff for solar power, householders now have a great choice of Government-backed financial incentives to choose from to best suit their clean energy needs.”

Launching the scheme, the Government Minister for Energy Greg Barker (pictured right) said: "Not only will people have warmer homes and cheaper fuel bills, they will reduce their carbon emissions, and get cash payments for installing these new technologies. It opens up a market for the supply chain, engineers and installers – generating growth and supporting jobs as part of our long-term economic plan."

Technologies and payments

The technologies currently covered by the scheme are:

• Biomass heating systems, which burn fuel such as wood pellets, chips or logs to provide central heating and hot water in a home. Biomass-only boilers are designed to provide heating using a ‘wet system’ (eg through radiators) and provide hot water. Pellet stoves with integrated boilers are designed to burn only wood pellets and can heat the room they are in directly, as well as provide heat to the rest of the home using a ‘wet system’ (eg through radiators) and provide hot water.
• Ground or water source heat pumps, which extract heat from the ground or water. This heat can then be used to provide heating and/or hot water in a home.
• Air to water heat pumps, which absorb heat from the outside air. This heat can then be used to provide heating and/or hot water in a home.
• Solar thermal panels, which collect heat from the sun and use it to heat up water which is stored in a hot water cylinder. The two types of panels that are eligible are evacuated tube panels and liquid-filled flat plate panels.

Technology	Tariff
Air-source heat pumps	7.3p/kWh
Ground and water-source heat pumps	18.8p/kWh
Biomass-only boilers and biomass pellet stoves with integrated boilers	12.2p/kWh
Solar thermal panels (flat plate and evacuated tube for hot water only)	19.2 p/kWh

Only one space heating system is allowed per property but homeowners can apply for solar thermal for hot water and a space heating system.

The guaranteed payments are made quarterly over seven years for households in England, Wales and Scotland. (Northern Ireland has its own RHI scheme). The scheme is designed to bridge the gap between the cost of fossil fuel heat sources and renewable heat alternatives.
According to renewable energy expert Richard Hiblen, who has more than 14 years’ experience in this field, the RHI tariffs are ‘good for some and better for others’, but even the worst figures make the technologies more attractive than installing oil or LPG heating.

Phil Hurley, managing director, NIBE Energy Systems Ltd., a renewable heating manufacturer, called the RHI "a game changer for the renewable heating industry". He continued: “The introduction of the domestic RHI gives the industry the security and confidence it needs to realise its growth potential".

But Neil Schofield, Head of External and Governmental Affairs at boiler (furnace) manufacturer Worcester, Bosch Group, cautioned that: “the funding is weighted heavily in favour of biomass, which is one of the most expensive systems to install and one requiring the largest amount of user intervention. Questions have already been raised over whether DECC has backed the right horse in this respect."

UK Solar Strategy

Earlier this week, the UK Government also launched its Solar Strategy, which contains plans to turn the Government estate as well as factories, supermarkets and car parks in cities around the UK into “solar hubs”.

Energy Minister Greg Barker  said he believes that “there is massive potential to turn our large buildings into power stations and we must seize the opportunity this offers to boost our economy as part of our long term economic plan. Solar not only benefits the environment, it will see British job creation and deliver the clean and reliable energy supplies that the country needs at the lowest possible cost to consumers.”

The UK has an estimated 250,000 hectares of south-facing commercial rooftops, and the government believes that solar increasingly offers efficient and cost effective onsite generation opportunities to both businesses and domestic consumers.

In a further initiative, the Department for Education is working on ways to improve energy efficiency across the 22,000 schools in England, to reduce their annual energy spend of £500 million, and to encourage the deployment of PV on schools alongside promoting energy efficiency. The British Education Secretary Michael Gove said: “Solar panels are a sensible choice for schools, particularly in terms of the financial benefits they can bring. It is also a great way for pupils to engage with environmental issues and think about where energy comes from.”